During operation of a mobile terminal, the mobile terminal may periodically detect received signal strength of a plurality of base stations that can be accessed, and determine whether the received signal strength of the currently accessed base station is the maximum among the plurality of base stations. If the received signal strength of the currently accessed base station is the maximum among the plurality of base stations, the mobile terminal may maintain access to the currently accessed base station; otherwise, the mobile terminal may perform a process to access the base station having the maximum received signal strength. Thus, the mobile terminal may access the base station having the maximum received signal strength, and the communication quality may be maintained.
However, a counterfeit base station may exist sometimes. Within a certain range, the received signal strength of the counterfeit base station may be greater than that of a genuine base station. As a result, the mobile terminal may access the counterfeit base station, and then the counterfeit base station may send a scam text message to the accessed mobile terminal to obtain illegal gains.